Sale Price:
$40.00
Original Price:
$50.00
ARP Harmonic Balancer / Crankshaft Bolt – GM LS & LT Wet-Sump #234-2503
When you’re spinning an LT to big RPM, and trying to get all that stump pulling torque to the wheels, then you need fasteners that work as hard as you do.
The OEM GM crank bolt is a torque-to-yield (TTY) fastener – it’s designed to stretch once, then get thrown away. Every time you pull the balancer for a cam swap, damper upgrade, or front cover service, you’re supposed to replace it. That’s fine for stock power, but when up the boost, you need alot more attention paid to keeping that LT held together with ARP high performance fasteners.
The ARP 234-2503 Harmonic Damper Bolt is a purpose-built upgrade for GM Gen 3/4 LS and select Gen 5 LT wet-sump engines, engineered from 8740 chromoly and rated at ~200,000 psi tensile strength. That means dramatically higher clamping force and far more safety margin than the factory TTY bolt – and unlike the OEM hardware, the ARP bolt is torque-to-spec and reusable, saving you time and $$$ down the road.
Pair it with your ATI damper and DMS lower pulley from Griffin Motorsports and you get a crank snout interface you can actually trust at elevated boost, RPM, and higher track temps.
Why Upgrade from the OEM Crank Bolt?
1. TTY vs. real clamp load
OEM bolt: torque-to-yield, designed to stretch once and be discarded. Every removal means buying another single-use bolt.
ARP 234-2503: torque-to-spec, reusable, and significantly stronger than stock, with 200,000 psi tensile strength.
That higher tensile strength allows more consistent clamping force on the damper and lower pulley, reducing the risk of the balancer walking, fretting, or coming loose under hard use.
2. Better design for real-world wrenching
ARP’s kit includes:
12-point, extra-tall head – accepts a deep socket and resists rounding/stripping when you’re leaning on a big breaker bar or torque wrench.
¼" thick wide-area washer – spreads load evenly over the face of the damper/pulley stack, improving surface pressure distribution and helping prevent galling or deforming the face of the damper.
3. Built for power, rpm and abuse
As the crankshaft flexes and twists, the harmonic balancer is absorbing huge amounts of kinetic energy every cycle. ARP’s damper bolts are specifically designed to lock the balancer to the crank under those conditions – especially important with and overdrive lower pulley (8.8"–10")
This isn’t just a “nice bolt.” It’s a critical safety component in the front of your rotating assembly.
Construction & Specs
From ARP’s LS/LT catalog and tech data:
*Material: 8740 chromoly steel
*Finish: Black oxide
*Tensile Strength: ~200,000 psi
*Head Style: 12-point, extra-tall
*Thread Size: M16 x 2.00
*Under-Head Length: ~4.325–4.33" (110 mm)
*Washer: ¼" thick, wide-area washer included
*Torque (with ARP Ultra-Torque lube): ~235 ft-lbs (per distributor data – always follow current ARP instructions)
Key functional advantages:
Higher yield strength = higher allowable clamp load before the bolt permanently deforms.
Chromoly + heat treatment = much better fatigue resistance under torsional cycling than stock.
Black oxide coating = corrosion resistance and improved consistency under torque.
Fitment Guide
Engine Compatibility (summary)
According to ARP and multiple LS/LT distributors, this kit is designed for:
Gen 3 & Gen 4 GM LS (wet-sump, except LS7): 4.8L, 5.3L, 5.7L, 6.0L, 6.2L small-block LS engines
Example engine codes: LS1, LS2, LS3, LS6, LQ4, LQ9, L76, L77, L92, L94, L96, LM7, LR4, L59, LY5, LY6, LMG, LMF, etc.
Select Gen 5 LT (wet-sump) applications: Gen V LT1 / LT4 wet-sump engines (e.g., Camaro platforms and certain truck/SUV 5.3L/6.2L) – not the dry-sump Corvette packages.
Typical vehicle examples (not exhaustive):
* 1998–2002 Camaro / Firebird LS1
* 1997–2004 C5 Corvette LS1/LS6
* 2005–2013 C6 Corvette LS2/LS3 (wet-sump)
* 2004–2007 CTS-V LS6/LS2, 2008–2015 LS3-based cars
* 1999–2013 Silverado / Sierra / Escalade / Tahoe / Suburban / Yukon LS-based truck engines
* 2010–2015 Camaro SS (LS3/L99)
*2016+ Camaro SS (LT1 – wet sump)
*2017+ Camaro ZL1 (LT4 – wet sump)
Important notes: Does not fit LS7 / LS9 or dry-sump LS/LT engines (e.g., many Corvette Z06/Z51/ZR1 applications). Those use ARP #234-2504 instead.
Installation & Usage Notes
Always clean crank snout threads and bolt threads before installation.
Use ARP Ultra-Torque assembly lube under the head and on threads for consistent clamp load.
Torque in stages to the final ARP-specified value (commonly around 235 ft-lbs with their lube – but follow the current instructions in your kit).
If you’re running an aftermarket damper and overdrive lower pulley, verify stack height and washer contact area before final torque.
If you’re not sure whether your combo is wet- or dry-sump, or which ARP bolt is correct for your build, reach out to us at info@griffin-motorsports.com – we can help you spec the right hardware, damper, and pulley combo for your goals.
ARP Harmonic Balancer / Crankshaft Bolt – GM LS & LT Wet-Sump #234-2503
When you’re spinning an LT to big RPM, and trying to get all that stump pulling torque to the wheels, then you need fasteners that work as hard as you do.
The OEM GM crank bolt is a torque-to-yield (TTY) fastener – it’s designed to stretch once, then get thrown away. Every time you pull the balancer for a cam swap, damper upgrade, or front cover service, you’re supposed to replace it. That’s fine for stock power, but when up the boost, you need alot more attention paid to keeping that LT held together with ARP high performance fasteners.
The ARP 234-2503 Harmonic Damper Bolt is a purpose-built upgrade for GM Gen 3/4 LS and select Gen 5 LT wet-sump engines, engineered from 8740 chromoly and rated at ~200,000 psi tensile strength. That means dramatically higher clamping force and far more safety margin than the factory TTY bolt – and unlike the OEM hardware, the ARP bolt is torque-to-spec and reusable, saving you time and $$$ down the road.
Pair it with your ATI damper and DMS lower pulley from Griffin Motorsports and you get a crank snout interface you can actually trust at elevated boost, RPM, and higher track temps.
Why Upgrade from the OEM Crank Bolt?
1. TTY vs. real clamp load
OEM bolt: torque-to-yield, designed to stretch once and be discarded. Every removal means buying another single-use bolt.
ARP 234-2503: torque-to-spec, reusable, and significantly stronger than stock, with 200,000 psi tensile strength.
That higher tensile strength allows more consistent clamping force on the damper and lower pulley, reducing the risk of the balancer walking, fretting, or coming loose under hard use.
2. Better design for real-world wrenching
ARP’s kit includes:
12-point, extra-tall head – accepts a deep socket and resists rounding/stripping when you’re leaning on a big breaker bar or torque wrench.
¼" thick wide-area washer – spreads load evenly over the face of the damper/pulley stack, improving surface pressure distribution and helping prevent galling or deforming the face of the damper.
3. Built for power, rpm and abuse
As the crankshaft flexes and twists, the harmonic balancer is absorbing huge amounts of kinetic energy every cycle. ARP’s damper bolts are specifically designed to lock the balancer to the crank under those conditions – especially important with and overdrive lower pulley (8.8"–10")
This isn’t just a “nice bolt.” It’s a critical safety component in the front of your rotating assembly.
Construction & Specs
From ARP’s LS/LT catalog and tech data:
*Material: 8740 chromoly steel
*Finish: Black oxide
*Tensile Strength: ~200,000 psi
*Head Style: 12-point, extra-tall
*Thread Size: M16 x 2.00
*Under-Head Length: ~4.325–4.33" (110 mm)
*Washer: ¼" thick, wide-area washer included
*Torque (with ARP Ultra-Torque lube): ~235 ft-lbs (per distributor data – always follow current ARP instructions)
Key functional advantages:
Higher yield strength = higher allowable clamp load before the bolt permanently deforms.
Chromoly + heat treatment = much better fatigue resistance under torsional cycling than stock.
Black oxide coating = corrosion resistance and improved consistency under torque.
Fitment Guide
Engine Compatibility (summary)
According to ARP and multiple LS/LT distributors, this kit is designed for:
Gen 3 & Gen 4 GM LS (wet-sump, except LS7): 4.8L, 5.3L, 5.7L, 6.0L, 6.2L small-block LS engines
Example engine codes: LS1, LS2, LS3, LS6, LQ4, LQ9, L76, L77, L92, L94, L96, LM7, LR4, L59, LY5, LY6, LMG, LMF, etc.
Select Gen 5 LT (wet-sump) applications: Gen V LT1 / LT4 wet-sump engines (e.g., Camaro platforms and certain truck/SUV 5.3L/6.2L) – not the dry-sump Corvette packages.
Typical vehicle examples (not exhaustive):
* 1998–2002 Camaro / Firebird LS1
* 1997–2004 C5 Corvette LS1/LS6
* 2005–2013 C6 Corvette LS2/LS3 (wet-sump)
* 2004–2007 CTS-V LS6/LS2, 2008–2015 LS3-based cars
* 1999–2013 Silverado / Sierra / Escalade / Tahoe / Suburban / Yukon LS-based truck engines
* 2010–2015 Camaro SS (LS3/L99)
*2016+ Camaro SS (LT1 – wet sump)
*2017+ Camaro ZL1 (LT4 – wet sump)
Important notes: Does not fit LS7 / LS9 or dry-sump LS/LT engines (e.g., many Corvette Z06/Z51/ZR1 applications). Those use ARP #234-2504 instead.
Installation & Usage Notes
Always clean crank snout threads and bolt threads before installation.
Use ARP Ultra-Torque assembly lube under the head and on threads for consistent clamp load.
Torque in stages to the final ARP-specified value (commonly around 235 ft-lbs with their lube – but follow the current instructions in your kit).
If you’re running an aftermarket damper and overdrive lower pulley, verify stack height and washer contact area before final torque.
If you’re not sure whether your combo is wet- or dry-sump, or which ARP bolt is correct for your build, reach out to us at info@griffin-motorsports.com – we can help you spec the right hardware, damper, and pulley combo for your goals.
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